I come to this forum with my head hung low. Quick details: I have a 2000 F-350 PSD, 400K miles (maintenance and repairs always done). I have problems with it stumbling/hesitating at 35-45 mph. Above that speed or below it runs fine. When you punch the accelerator down it clears up. I did the Hutch mod, new fuel pump, new fuel filter, new UVCH gasket and wiring harness, 50c mod, New ICP, cleaned fuel bowl, new EBP sensor and cleaned tube, HPOP shows 3/4 level on the oil. It still does the same. I have taken it to 4 so-called diesel mechanics and all claim different problems (more like guesses IMHO). $2000 later the only DTC that comes up is a Turbo Boost Pressure is low. One mechanic tells me I need a new turbo, the other claims fuel injectors, the other 2 recommended I "live with it". When I try towing a 8k trailer it won't do it. There is NO colored smoke out the tailpipe. I decided to bite the bullet and take it to a specialty diesel shop here in SW Michigan. Sadly they are so backed up they can't get to it for 2-3 weeks. This is a work truck and I need it to pull trailers. I am at my wits end. Does anyone know of a GOOD PSD shop around SW Michigan (St. Joseph, Kalamazoo, South Bend, Indiana)? I feel I need someone that truly understands the PSD and their wonderful quirks and not just a general diesel mechanic. Getting someone to do a buzz test seems impossible and now my budget is so low I can't afford a scanner. Or someone from this forum that has more knowledge than I do about the PSD and would be willing to come take a look at it (of course I would compensate). Any help is appreciated. Thank you.